github.com/gopherd/gonum@v0.0.4/lapack/testlapack/dorg2l.go (about)

     1  // Copyright ©2016 The Gonum Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package testlapack
     6  
     7  import (
     8  	"testing"
     9  
    10  	"math/rand"
    11  
    12  	"github.com/gopherd/gonum/blas/blas64"
    13  )
    14  
    15  type Dorg2ler interface {
    16  	Dorg2l(m, n, k int, a []float64, lda int, tau, work []float64)
    17  	Dgeql2er
    18  }
    19  
    20  func Dorg2lTest(t *testing.T, impl Dorg2ler) {
    21  	const tol = 1e-14
    22  
    23  	rnd := rand.New(rand.NewSource(1))
    24  	for _, test := range []struct {
    25  		m, n, k, lda int
    26  	}{
    27  		{5, 4, 3, 0},
    28  		{5, 4, 4, 0},
    29  		{3, 3, 2, 0},
    30  		{5, 5, 5, 0},
    31  		{5, 4, 3, 11},
    32  		{5, 4, 4, 11},
    33  		{3, 3, 2, 11},
    34  		{5, 5, 5, 11},
    35  	} {
    36  		m := test.m
    37  		n := test.n
    38  		k := test.k
    39  		lda := test.lda
    40  		if lda == 0 {
    41  			lda = n
    42  		}
    43  
    44  		a := make([]float64, m*lda)
    45  		for i := range a {
    46  			a[i] = rnd.NormFloat64()
    47  		}
    48  		tau := nanSlice(max(m, n))
    49  		work := make([]float64, n)
    50  		impl.Dgeql2(m, n, a, lda, tau, work)
    51  
    52  		impl.Dorg2l(m, n, k, a, lda, tau[n-k:], work)
    53  
    54  		q := blas64.General{Rows: m, Cols: n, Data: a, Stride: lda}
    55  		if resid := residualOrthogonal(q, false); resid > tol {
    56  			t.Errorf("Case m=%v, n=%v, k=%v, lda=%v: columns of Q not orthonormal; resid=%v, want<=%v", m, n, k, lda, resid, tol)
    57  		}
    58  	}
    59  }